feat: Phase 2 complete — calls, media, spaces, persistence, chat improvements

- LiveKit/MatrixRTC voice+video calls with full call screen UI
- Incoming call overlay (accept/decline)
- Media upload/download — file picker, image rendering, file download
- Spaces navigation — space list + expandable child rooms
- Drift persistence — rooms + messages written on every sync
- Sync persistence auto-starts on login and session restore
- Chat: typing indicators, long-press menu, reply, emoji reactions
- User search dialog + start DM from rooms screen
- Android: INTERNET + CAMERA + RECORD_AUDIO permissions in main manifest
- Emoji picker for reactions

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/core/storage/database.dart

@@ -0,0 +1,142 @@
+// Version: 1.1.0 | Created: 2026-04-01
+// Drift database — rooms and messages tables.
+// Uses driftDatabase() from drift_flutter for cross-platform support:
+//   - Mobile/desktop: SQLite file via sqlite3_flutter_libs
+//   - Web: OPFS (Origin Private File System) via IndexedDB fallback
+
+import 'package:drift/drift.dart';
+import 'package:drift_flutter/drift_flutter.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'database.g.dart';
+
+// ---------------------------------------------------------------------------
+// Table definitions
+// ---------------------------------------------------------------------------
+
+/// Persisted room state. Upserted on every sync.
+class RoomsTable extends Table {
+  @override
+  String get tableName => 'rooms';
+
+  TextColumn get id => text()();
+  TextColumn get name => text()();
+  TextColumn get avatarUrl => text().nullable()();
+  TextColumn get lastMessage => text().nullable()();
+  IntColumn get lastActivityAt =>
+      integer().nullable()(); // milliseconds since epoch
+  IntColumn get unreadCount => integer().withDefault(const Constant(0))();
+  BoolColumn get isDm => boolean().withDefault(const Constant(false))();
+
+  @override
+  Set<Column<Object>> get primaryKey => {id};
+}
+
+/// Persisted message events. Upserted when received from sync.
+class MessagesTable extends Table {
+  @override
+  String get tableName => 'messages';
+
+  TextColumn get id => text()(); // eventId
+  TextColumn get roomId => text()();
+  TextColumn get senderId => text()();
+  TextColumn get body => text().nullable()();
+  TextColumn get type => text()(); // MessageType name
+  IntColumn get timestamp => integer()(); // milliseconds since epoch
+  TextColumn get rawJson => text()(); // full event JSON for future use
+
+  @override
+  Set<Column<Object>> get primaryKey => {id};
+}
+
+// ---------------------------------------------------------------------------
+// Database class
+// ---------------------------------------------------------------------------
+
+@DriftDatabase(tables: [RoomsTable, MessagesTable])
+class AppDatabase extends _$AppDatabase {
+  AppDatabase() : super(driftDatabase(name: 'm8chat'));
+
+  // Separate constructor for testing — accepts a custom executor.
+  AppDatabase.forTesting(super.executor);
+
+  @override
+  int get schemaVersion => 1;
+}
+
+// ---------------------------------------------------------------------------
+// DAOs
+// ---------------------------------------------------------------------------
+
+/// Data access for rooms.
+extension RoomsDao on AppDatabase {
+  /// Insert or replace a room row.
+  Future<void> upsertRoom(RoomsTableCompanion room) =>
+      into(roomsTable).insertOnConflictUpdate(room);
+
+  /// Watch all rooms ordered by unread count desc then last activity desc.
+  Stream<List<RoomsTableData>> watchAllRooms() {
+    return (select(roomsTable)..orderBy([
+          (t) =>
+              OrderingTerm(expression: t.unreadCount, mode: OrderingMode.desc),
+          (t) => OrderingTerm(
+            expression: t.lastActivityAt,
+            mode: OrderingMode.desc,
+            nulls: NullsOrder.last,
+          ),
+        ]))
+        .watch();
+  }
+
+  /// Get a single room by id, or null if not found.
+  Future<RoomsTableData?> getRoomById(String id) =>
+      (select(roomsTable)..where((t) => t.id.equals(id))).getSingleOrNull();
+}
+
+/// Data access for messages.
+extension MessagesDao on AppDatabase {
+  /// Insert or replace a message row.
+  Future<void> upsertMessage(MessagesTableCompanion message) =>
+      into(messagesTable).insertOnConflictUpdate(message);
+
+  /// Watch all messages for [roomId] ordered oldest-first.
+  Stream<List<MessagesTableData>> watchByRoom(String roomId) {
+    return (select(messagesTable)
+          ..where((t) => t.roomId.equals(roomId))
+          ..orderBy([
+            (t) =>
+                OrderingTerm(expression: t.timestamp, mode: OrderingMode.asc),
+          ]))
+        .watch();
+  }
+
+  /// Load one page of messages for [roomId], most recent first.
+  Future<List<MessagesTableData>> getPage(
+    String roomId, {
+    int limit = 50,
+    int offset = 0,
+  }) {
+    return (select(messagesTable)
+          ..where((t) => t.roomId.equals(roomId))
+          ..orderBy([
+            (t) =>
+                OrderingTerm(expression: t.timestamp, mode: OrderingMode.desc),
+          ])
+          ..limit(limit, offset: offset))
+        .get();
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Riverpod provider
+// ---------------------------------------------------------------------------
+
+/// Provides the singleton [AppDatabase]. keepAlive: true — opened once for
+/// the app lifetime.
+@Riverpod(keepAlive: true)
+AppDatabase appDatabase(Ref ref) {
+  final db = AppDatabase();
+  // Close the database when the provider is finally disposed (app shutdown).
+  ref.onDispose(db.close);
+  return db;
+}